Nolan wouldn't have bothered with Rises if that was the case. Movie came out four years after The Dark Knight and no matter what he did, it wasn't going to live up to that film. Nolan probably had a great idea for the movie and some people ended up just not feeling it. It happens . Raimi on the other hand obviously phoned in Spider-Man 3. The novelization is better than both versions of that movie they put out.
Nolan didn't want to make a third Batman movie without Heath.
WB wanted a third batman movie made and wanted Nolan to direct it. He wanted to do Inception but could only do it with a large budget.
He most likely did The Dark Knight Rises so that he would be given the required budget for Inception.
Inception had a big budget but was not expected to even be a hit and was even expected to flop.